This application is based on and claims priority to Japanese Patent Application No. Hei 11-283238, filed Oct. 4, 1999, the entire contents of which is hereby expressly incorporated by reference.
1. Field of the Invention
The present invention principally relates to engines for powering an outboard motor. More particularly, the present invention relates to an arrangement of certain components for such engines associated with outboard motors.
2. Description of the Related Art
Outboard motors are often used to power watercraft. The motors are attached to the transom of the watercraft and include an engine disposed within a power head of the motor. The engine drives a propulsion unit and is thus able to push the watercraft through water.
The powerhead of the outboard motor comprises the engine enclosed within a cowling. The power head usually extends above a transom of the watercraft. As such, the power head can be a significant source of wind drag for the watercraft. Also, a large power head may obstruct the watercraft operator""s field of vision.
Various structural designs are used to decrease the size of the power head. For example, a V-type cylinder arrangement allows the engine height to be decreased. However, V-type engines tend to be relatively wide because of the inclined cylinder banks. Additionally, electrical components such as an engine control unit (ECU), a relay box and a fuse box, have traditionally been mounted on the side of the engine. Additionally, in 4-stroke, V-type engines, the intake pipes, as well as the oil filter, are generally situated on the sides of the engine. With all these components situated on the sides of the engines, 4-stroke, V-type engines tend to be quite wide.
Accordingly, there is a need in the art for an arrangement of engine components of an outboard motor that will decrease the width of the motor and provide satisfactory mounting positions for the components.
In accordance with one aspect, the present inventions includes an outboard motor having a four-stroke engine and an induction system. The engine has a first bank of cylinders and a second bank of cylinders arranged generally in a xe2x80x9cVxe2x80x9d formation. Each cylinder bank defines a plurality of cylinder bores, which communicate with a crankcase. A piston is reciprocatably disposed in each cylinder bore and drives a substantially vertically-oriented crankshaft disposed in the crankcase. Each cylinder bank has a cylinder head attached thereto, which cylinder head has at least one intake port formed therethrough and opening into an associated cylinder bore. A forward side of the crankcase is defined opposite the cylinder head. The induction system comprises an intake silencer and a plurality of runners extending from the intake silencer to each of the intake ports. The intake silencer is positioned forwardly of the crankcase. An electrical component is mounted on a front surface of the crankcase.
In accordance with another aspect of the present invention, a watercraft comprises an outboard motor and a battery. The outboard motor is mounted onto a transom of the watercraft and comprises an internal combustion engine and an induction system for providing air to a combustion chamber of the engine. The engine has a substantially vertical crankshaft at least partially enclosed within a crankcase. At least a portion of the induction system is positioned forwardly of a front side of the crankcase. An electrical grounding line extends from the battery to the front side of the crankcase. At least one electrical component is positioned between the crankcase and the intake silencer.
In accordance with yet another aspect, the present invention includes an outboard motor comprising an internal combustion engine and an induction system enclosed within a cowling. The engine has an engine body which defines at least one combustion chamber and a crankcase. The crankcase at least partially encloses a substantially vertically-oriented crankshaft therein. The engine body has a front end substantially opposite the at least one combustion chamber. At least a portion of the induction system is disposed forwardly of the front end of the engine body. At least one electrical component is disposed between the front end of the engine body and the portion of the induction system disposed forwardly of the engine body.
Further aspects, features and advantages of this invention will become apparent from the detailed description of the preferred embodiment which follows.